DOI: 10.11118/978-80-7701-048-1-0225

SUSTAINABLE FABRICATION OF CELLULOSE-BASED ANTIBACTERIAL NANOCOMPOSITE FILMS FOR ACTIVE PACKAGING TO PREVENT LISTERIA AND SALMONELLA CONTAMINATION

Pratiksha Shrestha¹, Qinglin Wu², Abouzeid, Ragab Esmail Mahmoud², Witoon Prinyawiwatkul¹, Karuna Kharel¹

¹ School of Nutrition and Food Sciences, Louisiana State University AgCenter, Baton Rouge, Louisiana, USA

² School of Renewable Natural Resources, Louisiana State University AgCenter, Baton Rouge, Louisiana, USA

Packaged low moisture foods are prone to contamination by Listeria monocytogenes and Salmonella spp. indicating a need for post-process intervention. Sustainable antimicrobial packaging using cellulose-based biomaterials incorporated with natural antimicrobials offers a promising solution for controlled antimicrobial release and effective pathogen mitigation. This study aimed to develop an antimicrobial nanocomposite by incorporating natural antimicrobials into lignocellulose nanofibers derived from plant-based waste. Nisin (0.33%) and oregano essential oil (OEO) at three different concentrations (0.5%, 1%, 1.5% were used to prepare 3 different formulations of lignocellulose nanofiber (LCNF) based nanocomposite films by solution casting on Teflon plates. The films were eventually punched into 9 mm disks for antimicrobial tests. In vitro antimicrobial activity was tested using disk diffusion method against four Salmonella enterica strains (PT 30, PT 9c, Oranienberg, Anatum), four Listeria monocytogenes strains (Scott A, V7, LCDC, 101M) and control on Mueller-Hinton agar. Film color was evaluated using L*, a*, b* colorimetric system. Differences in mean values were analyzed using ANOVA with post-hoc Tukey’s test at P<0.05 in JMP® Pro 18.0.1. The antimicrobial film demonstrated broad-spectrum efficacy, with zone of inhibition ranging from 13.4–25.5 mm. It was significantly more effective (P<0.05) against Gram-positive bacteria, as evidenced by greater susceptibility of L. monocytogenes (19.11 ± 0.26 mm) compared to S. enterica (15.97 ± 0.26 mm). Among the tested strains, the most resistant were Salmonella PT 30 and Oranienberg (14.5–16.0 mm), while the most susceptible were L. monocytogenes Scott A and V7 (20.57–21.24 mm). For both organisms, the 15% OEO concentration showed the highest efficacy (P<0.05), though films at this concentration had a slightly darker color, as indicated by a significantly lower L* value (70.27±0.28). Plant-based nanocomposite antimicrobial films offer a promising sustainable solution for enhancing food safety in packaged ready to eat low moisture foods, highlighting the need for further research.

Keywords: food packaging, antimicrobial properties, nanocomposite films

pages: 225-225, online: 2025